AB1441 CLINICAL CHARACTERISTICS OF PEDIATRIC PATIENTS WITH RHEUMATIC DISEASES UNDER TREATMENT WITH BIOLOGICAL THERAPY: INFORMATION FROM BIOBADAMEX
Authors: S. Mendieta, A. Torres, F. Irazoque-Palazuelos, S. Sicsik, I. J. Colunga-Pedraza, D. X. Xibille Friedmann, D. Alpizar-Rodriguez, V. Rivera Teran
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> The advent of biologic treatment (bDMARD) in childhood rheumatic diseases (RD) has changed their evolution and prognosis. Evidence is robust for diseases such as juvenile idiopathic arthritis (JIA) and systemic lupus erythematosus (SLE), but in other diseases we still have to learn which is the ideal therapy, time to discontinuation and the potential adverse events (AE) in short and long term. <h3>Objectives</h3> Identify the clinical and treatment characteristics of pediatric patients with rheumatic diseases with bDMARD treatment and describe the development of AE. <h3>Methods</h3> BIOBADAMEX is a prospective ongoing cohort of Mexican patients with RD using bDMARDs since 2016. We included all patients younger than 18 years of age registered in BIOBADAMEX. Descriptive statistics were used for the baseline characteristics and the Chi-square test to analyze the differences between the characteristics of the groups in relation to the development of AE. <h3>Results</h3> A total of 45 patients were included, 31 (69%) of them female, mean age of 13.3 (±3.6) years. (Table 1). The most frequent diagnosis was JIA 25 (56%), followed by SLE 9 (20%), uveitis 5 (11%), polymyositis/dermatomyositis and hidradenitis 2 (4%) respectively; systemic sclerosis and CINCA 1 patient (2%) respectively. The mean duration disease in years was 4.67 (±2.1). Nine patients (20%) used a biologic prior to the current; 23 (51%) patients had comorbidities. The most frequent bDMARDs used was Adalimumab (ADA) in 17 (38%) patients followed by Rituximab in 15 (33%) and Tocilizumab in 10 (22%), Infliximab, Abatacept and Canakinumab were used in one patient respectively. When compared by groups, ADA and Tocilizumab were the most used bDMARDs in JIA, Rituximab the only one used in SLE and PM/DM, and ADA the only one for uveitis. 15 patients discontinued biological treatment, 4 (27%) due to AE. 82% used an additional synthetic DMARD, being methotrexate the most used in 48% of patients. Steroids were used by 21 (47%) of the patients with a median dose of 10mg (IQR 5 - 25). Fifteen AEs were recorded: 7 (47%) were infections, 5 of these (71%) were COVID; allergies and neutropenia in 2 (13%) patients respectively. By disease infections were more frequent in patients with JIA and Uveitis; neutropenia only occurred in patients with JIA (p 0.95). 87% of the AEs were non-serious, 1 patient with JIA presented a severe AE and one patient with SLE a fatal AE associated with COVID (p 0.93), with no statistically significant difference between groups. <h3>Conclusion</h3> JIA is the most frequent indication to use bDMARD as worldwide reported. The AE in this analysis are similar to previous registries in terms of the prevalence of infections, in our group the most frequent infectious complication was COVID, being fatal in one patient related with rituximab in SLE. Our study did not find statistically significant differences in the development of AE between diseases; however, they will continue to be reported and the number of patients in the registry will increase. <h3>References</h3> [1] Sterba,Y.et al. Curr Rheumatol Rep 2016;18,45 [2] Fuhlbrigge RC, et al. 2021;47(4):531-543. <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> Samara Mendieta: None declared, Alfonso Torres: None declared, Fedra Irazoque-Palazuelos: None declared, Sandra Sicsik: None declared, Iris Jazmin Colunga-Pedraza: None declared, Daniel Xavier Xibille Friedmann: None declared, Deshire Alpizar-Rodriguez Employee of: Scientific advisor in GSK-Mexico, VIJAYA RIVERA TERAN: None declared.